Alamance County, NC Environmental Rules: Flood Elevation Requirements (2026)

6, Development Specific Provisions for Flood Hazard Reduction. Under the Residential Construction provision, new construction and substantial improvement of any residential structure, including manufactured homes, must have its reference level, including any basement, elevated no lower than the Regulatory Flood Protection Elevation. Article 2's definitions section pins down that number: it is the FEMA Base Flood Elevation plus two feet of freeboard in Special Flood Hazard Areas where a BFE has been determined, or at least two feet above the highest adjacent grade where none has been set.

Non-residential structures in Zones A, AE, AH, AO and A99 may floodproof to the Regulatory Flood Protection Elevation instead of elevating, but a registered professional engineer or architect must certify the floodproofing and file that certification, an operational plan, and an inspection and maintenance plan with the Floodplain Administrator. Manufactured homes must have their reference level at or above the same elevation and be anchored to resist flotation and lateral movement; chassis raised more than 36 inches require an engineering certification. Small accessory structures, those with a footprint under 150 square feet or representing an investment of $3,000 or less, are excused from the elevation and floodproofing standards if they meet anchoring and low-damage-potential criteria. 4, submitting a plot plan showing the Special Flood Hazard Area boundary and proposed reference-level elevations tied to NAVD 1988.